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Critical Error Audio Is Not Heard on an Abnormal Disconnect SIP Call

Problem Summary

A critical error wav file is not heard on an abnormal disconnect call. Instead the caller hears a fast busy condition, or the call just drops.

Error Message

None.

Possible Cause

When using REFER transfers, including the REFER used to play back critical error.wav for abnormal disconnects, an outbound voip dial peer is necessary on the ingress gateway. This outbound dial peer is needed because when the REFER message comes into gateway from Unified CVP Call Server, it needs to match an outbound dial peer in order for the call to succeed, or else a 503 rejection occurs if no dial peers match the REFER-TO header URI. Dial peer destination targets must match the labels in the REFER-TO SIP URI, that is <error DN>@<sip-server> and other labels that may be used in the Unified ICME routing label.

Recommended Action

Configure an outbound voip dial peer on the ingress gateway. For example: